Politicians are, of course, not the only ones who can get into difficulties with their statements, which can range from being just a little misleading to being distinctly "economical with the truth" (what most of us call "lying").

Ahead of the recent North American International Motor Show in Detroit, VW boss Matthias Müller got into trouble when he gave an interview in English to NPR. Müller said this of VW's communication with US regulators about the emissions scandal before it became public: "We didn't lie. We didn't understand the question first."

Some people have said Müller's English is not up to the necessary standard for communicating at the highest level about sensitive business topics. Listening to the interview and reading the transcript, it is clear that Müller's English is not perfect, but it is certainly not bad. His performance does, however, highlight some key lessons for German-speaking managers when using English internationally:

You don't need to speak perfectly, but you should aim to be perfectly clear. The goal of any communication - unless you are deliberately trying to confuse people - is that others understand both what you are saying and why you are saying it. This is a very ambitious goal, as it is almost impossible to communicate without being misunderstood. But it is a goal worth aiming at.

In many cases, minor grammatical mistakes are unimportant. For example, Müller said VW "reached targets with some software solutions which haven't been compatible to the American law". Strictly speaking, he should have said, "with some software solutions that weren't compatible with American law", but his meaning was clear despite the grammatical errors.

Sometimes, grammatical mistakes do change the meaning of what you are saying. Less clear was Müller's statement: "I am CEO in three months." This sounds as though he will take up the position of CEO in three months' time. It would have been clearer and more correct to say, "I have been CEO for three months."

An accent is not necessarily a barrier to communication. All native English-speakers have an accent of some sort. But as long as it is not very strong, this is not a problem. The same is true for non-native speakers. Matthias Müller clearly has a German accent when speaking English, just as I have an English accent when I speak German. But that in itself does not hinder communication. On the other hand, Müller does sound somewhat direct and abrupt, and could work on his intonation. If you are unsure whether your accent and intonation are getting in the way of communication, ask friends or colleagues for feedback.

Avoid complicated words and expressions unless you are sure that you have them right and your audience will understand them. Many speakers of English as a foreign language use sophisticated language as well as making basic grammar mistakes. For example, Müller said, "We'll do our utmost to do things right." Native speakers of English would understand "do our utmost" (unser Möglichstes tun), but many non-native speakers wouldn't recognize this expression. Think about your audience.